The present invention relates generally to a prosthesis, and more particularly to an apparatus and method for securing soft tissue to an artificial prosthesis.
During the lifetime of a patient, it may be necessary to perform a joint replacement procedure on the patient as a result of, for example, disease or trauma. Such a joint replacement procedure may involve the use of a prosthetic component or prosthesis to replace a portion of the patient""s natural bone. Heretofore designed prosthesis are generally constructed of a metallic or composite material. A problem arises when such metal or composite prosthesis are utilized to replace a relatively large portion of a bone. In particular, if a large portion of a patient""s natural bone must be replaced with a prosthesis, it is generally difficult to attach the soft tissue required for joint operation (e.g. ligaments and tendons) to the implanted prosthesis. For example, as a result of cancer or other type of disease, the entire proximal end portion of a patient""s tibia may have to be removed and replaced with a tibial prosthesis. In such a case, the natural point of connection for the distal end portion of the patient""s patellar ligament (i.e. the tibial tuberosity) is also removed. Hence, the distal end portion of the patient""s patellar ligament must then be secured to the tibial prosthesis in order to provide for functional operation of the patient""s knee.
A number of approaches have heretofore been taken in an attempt to attach soft tissue such as ligaments and tendons to a metal or composite prosthesis. The most common approach has been to configure the prosthesis with a number of suture holes to which the soft tissue (e.g. a ligament or tendon) may be sutured. One problem with this approach is that the soft tissue has no source of nourishment. Moreover, such a configuration of the prosthesis does not provide adequate surface features or the like for facilitating ingrowth or anchoring of the soft tissue to the prosthesis.
Another approach which has been utilized involves the use of an allograft or composite allograft prosthesis in lieu of a metal or composite prosthesis. Such prosthesis are generally harvested from a donor upon death thereof and then frozen until needed. However, the availability of allograft prostheses is becoming more and more scarce. Moreover, even when available, such harvested allograft prostheses often times do not possess the requisite number of tissue attachment sites. In addition, patients requiring the joint replacement procedure are sometimes either very large or very small in size which can make the procurement of a properly sized allograft prosthesis very difficult.
Yet another approach which has been utilized involves the use of bone plugs and grafts which are threaded into or otherwise secured to the prosthesis. However, this approach suffers from many of the same drawbacks as does the use of an allograft prosthesis. Moreover, since bone plugs are constructed of dead tissue, they tend to become brittle over time and eventually break down under heavy loads.
What is needed therefore is an apparatus and method for securing soft tissue to a prosthesis which overcomes one or more of the above-mentioned drawbacks. What is particularly needed is an apparatus and method for securing soft tissue to a prosthesis which provides enhanced mechanical anchoring of the soft tissue while also stimulating or otherwise facilitating tissue ingrowth.
In accordance with one embodiment of the present invention, there is provided an apparatus for securing soft tissue to a prosthesis. The apparatus includes a retaining member secured to the prosthesis. The apparatus also includes a first band constructed of a resorbable material. The first band has a first end portion, a middle portion, and a second end portion. The apparatus also includes a second band constructed of a biologically inert material. The second band has a first end portion, a middle portion, and a second end portion. The middle portion of the first band is positioned around a retaining portion of the retaining member such that both the first end portion and the second end portion of the first band extend outwardly from the retaining member. The middle portion of the second band is positioned around the retaining portion of the retaining member such that both the first end portion and the second end portion of the second band extend outwardly from the retaining member. Each of the first end portion of the first band, the second end portion of the first band, the first end portion of the second band, and the second end portion of the second band is adapted to be secured to the soft tissue.
In accordance with another embodiment of the present invention, there is provided an apparatus for securing soft tissue to a prosthesis. The apparatus includes a retaining member secured to the prosthesis. The retaining member has a retaining surface. The apparatus also includes an inner band having a first end portion, a middle portion, and a second end portion. The apparatus further includes an outer band having a first end portion, a middle portion, and a second end portion. The middle portion of the inner band is positioned in contact with the retaining surface of the retaining member such that both the first end portion and the second end portion of the inner band extend outwardly from the retaining member. The outer band is secured to the inner band such that (a) the first end portion of the outer band is positioned in contact with the first end portion of the inner band, (b) the middle portion of the outer band is positioned in contact with the middle portion of the inner band, and (c) the second end portion of the, outer band is positioned in contact with the second end portion of the inner band. Each of the first end portion of the inner band, the second end portion of the inner band, the first end portion of the outer band, and the second end portion of the outer band is adapted to be secured to the soft tissue.
In accordance with a further embodiment of the present invention, there is provided a method of securing soft tissue to a prosthesis. The prosthesis has a retaining member secured thereto. The method includes the step of looping a first end portion of a first band around the retaining member such that both the first end portion of the first band and a second end portion of the first band extend outwardly from the retaining member. The method also includes the step of looping a first end portion of a second band around the retaining member such that both the first end portion of the second band and a second end portion of the second band extend outwardly from the retaining member. In addition, the method includes the step of securing the soft tissue to (i) the first end portion and the second end portion of the first band, and (ii) the first end portion and the second end portion of the second band.
In accordance with yet another embodiment of the present invention, there is provided a prosthesis assembly. The prosthesis assembly includes a prosthetic component having a retaining member secured thereto. The prosthesis assembly also includes a first band constructed of a resorbable material. The first band is adapted to be secured to both the retaining member and the soft tissue. The prosthesis assembly also includes a second band constructed of a biologically inert material. The second band is adapted to be secured to both the retaining member and the soft tissue.
It is therefore an object of the present invention to provide a new and useful apparatus for securing soft tissue to a prosthesis.
It is moreover an object of the present invention to provide an improved apparatus for securing soft tissue to a prosthesis.
It is a further object of the present invention to provide a new and useful method of securing soft tissue to a prosthesis.
It is also an object of the present invention to provide an improved method of securing soft tissue to a prosthesis.
It is yet another object of the present invention to provide an apparatus and method for securing soft tissue to a prosthesis which provides enhanced mechanical anchoring of the soft tissue while also stimulating or otherwise facilitating tissue ingrowth.
The above and other objects, features, and advantages of the present invention will become apparent from the following description and the attached drawings.